KR102386803B1 - Color expression dbr film, and manufacturing method thereof - Google Patents

Abstract

The present application relates to a color-type DBR film manufactured through a low-temperature solution process, a manufacturing method thereof, and a CIGS solar cell to which the color-type DBR film is applied.

Description

COLOR EXPRESSION DBR FILM, AND MANUFACTURING METHOD THEREOF

The present application relates to a color-type DBR film manufactured through a low-temperature solution process, a manufacturing method thereof, and a CIGS solar cell to which the color-type DBR film is applied.

A solar cell is a device based on a semiconductor principle, and has a property of converting solar energy into electrical energy. The development of solar cells that can be applied to urban living structures, including building-integrated solar cells (BIPV) that can be used as an independent power source in the city, is a field with a large ripple effect as its marketability is expected.

In order to apply the solar cell to urban living structures, it must be a solar cell capable of maintaining high efficiency against light of various intensities as well as stability that can be operated outside for a long time. Dye-sensitized and organic solar cells can implement a variety of colors, but have low color purity due to a broad absorption spectrum, and require improved efficiency and stability for commercialization. Although perovskite solar cells have high efficiency, they need to secure stability, and there is a limitation in that it is difficult to realize various colors due to the nature of inorganic materials. CIGS solar cell is the most suitable solar cell among next-generation solar cells to be applied to urban structures mainly installed outside because of its high efficiency and stability, but it is difficult to realize various colors due to the nature of inorganic materials.

In order to apply solar cells to urban life structures, aesthetics are essential in addition to efficiency and stability. In order to realize the aesthetics of the next-generation CIGS solar cell, it is necessary to develop a design that can be applied to various urban living structures with permeability and various colors for CIGS solar cells. A method using internal reflection of a metal multilayer thin film (Fabry-Perot interferometer) and a distributed Bragg reflector (DBR) are used. Fabry-Perot interferometer has high color purity but low transmittance, so there is a problem in that a lot of efficiency reduction is inevitable while implementing color in solar cells. Therefore, in order to have high color purity and high transmittance characteristics at the same time, it is most ideal to use a Distributed Bragg reflector (hereinafter referred to as DBR) having a narrow bandwidth (FWHM) absorption at a desired wavelength. . However, in order to construct a DBR, a high cost is required because a multilayer thin film of several layers is usually manufactured by a vacuum process. Color-type solar cells to which are applied have a problem that has not yet been commercialized due to low economic feasibility.

Republic of Korea Patent Publication No. 10-2018-0076890

An object of the present application is to provide a color-type DBR film manufactured through a low-temperature solution process, a manufacturing method thereof, and a CIGS solar cell to which the color-type DBR film is applied.

However, the problems to be solved by the present application are not limited to the problems mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art from the following description.

A first aspect of the present disclosure provides a method for forming a first layer through a solution process of a first solution comprising a first layer precursor material; and forming a second layer through a solution process of a second solution containing a second layer precursor material, thereby preparing a unit laminate.

A second aspect of the present application is a color-type DBR film produced through the method for manufacturing a DBR film according to the first aspect, and expresses blue, green, and red colors by controlling the thickness of the first layer, the second layer, or both. It provides a color-type DBR film.

A third aspect of the present application provides a CIGS solar cell to which the color DBR film according to the second aspect is applied.

In the embodiments of the present application, since the color filter of the prior art is used in a CIGS solar cell, there is a problem in that color purity and light transmittance are lowered, or there is a problem in that the process cost is high because it is manufactured through a deposition process. However, the method for manufacturing a DBR filter according to the present invention has the effect of manufacturing a multilayer thin film through a low-temperature continuous solution process, which can be performed at low cost and a large-area DBR filter can be manufactured.

In the embodiments of the present application, since the color DBR film according to the present application is a flexible polymer-based film, it has a feature that can be applied to a solar cell module of a curved surface rather than a flat surface.

The color DBR film according to the embodiments of the present application has high light transmittance when applied to a building-integrated solar cell, so that the efficiency of the solar cell can be maintained within 10% without lowering the efficiency, and at the same time a narrow reflection wavelength width (FWHM) It is possible to express colors with high color purity by implementing the

1 is a schematic diagram showing a manufacturing strategy of a DBR film using a low-temperature solution process in one embodiment of the present application.
2 is a schematic diagram showing the structure of a DBR film in one embodiment of the present application.
3A is a graph showing reflectance (i) and CIE data (ii) according to the number of stacks in the DBR film (blue) according to an embodiment of the present application.
3B is a graph showing reflectance (i) and CIE data (ii) according to the number of stacks in the DBR film (green) according to an embodiment of the present application.
3C is a graph showing reflectance (i) and CIE data (ii) according to the number of stacks in the DBR film (red) according to an embodiment of the present application.
Figure 4a is a graph showing the reflectance of each wavelength band in the 37 layer in the DBR film according to an embodiment of the present application.
Figure 4b is a graph showing CIE data of each wavelength band in the 37 layer in the DBR film according to an embodiment of the present application.
4c is a photograph showing color expression in the 37th layer in the DBR film according to an embodiment of the present application.
5 is a SEM photograph of a cross section of the film in the DBR film according to an embodiment of the present application.
Figure 6a, in the DBR film (blue) according to an embodiment of the present application, in the case of a large area of 5 cm X 5 cm, the reflectance (i) according to the number of layers and shows a color expression photograph (ii) thereof.
Figure 6b, in the DBR film (green) according to an embodiment of the present application, in the case of a large area of 5 cm X 5 cm, the reflectance (i) according to the number of layers and shows the color expression photograph (ii) thereof.
6c is a graph showing CIE data in the case of a large area of 5 cm X 5 cm in the DBR film according to an embodiment of the present application.
6d is, in the DBR film ((i) and (ii)) according to an embodiment of the present application, the center (X ₁ , X ₄ ), the center in the color expression photograph in the case of a large area of 5 cm X 5 cm It is a photograph showing the position at a radius of 1.5 cm (X ₂ , X ₅ ) and at a radius of 3 cm from the center (X ₃ , X ₆ ).
6e is a graph showing reflectance according to each position in the case of a large area of 5 cm X 5 cm in the DBR film according to an embodiment of the present application.
7 is a graph showing reflectance measured with a confocal microscope in a CIGS solar cell to which a DBR film according to an embodiment of the present application is applied.
8A is a photograph showing the appearance according to the number of layers in the CIGS solar cell to which the DBR film according to an embodiment of the present application is applied.
8b is a photograph showing the appearance according to the number of layers in the substrate to which the DBR film according to an embodiment of the present application is applied;
9A is a photograph showing each point measured with a confocal microscope in a CIGS solar cell to which a DBR film according to an embodiment of the present application is applied.
FIG. 9b is a graph comparing reflectance spectra of a DBR simulated by MATLAB at each point, a CIGS solar cell to which a DBR film is applied, and a glass substrate in one embodiment of the present application.
FIG. 9c is a graph comparing reflectance spectra of a DBR simulated by MATLAB at each point, a CIGS solar cell to which a DBR film is applied, and a glass substrate in an embodiment of the present application.
FIG. 9d is a graph comparing reflectance spectra in a CIGS solar cell to which a DBR film is applied and a DBR simulated by MATLAB at each point, and a glass substrate, in an embodiment of the present application.
10A is a photograph showing a spin coater using a chuck made of a metal and a DBR film manufactured through the spin coater in the prior art.
FIG. 10b is a photograph showing a spin coater using a chuck made of polypropylene and a DBR film manufactured through the spin coater according to an embodiment of the present application.
11A is a photograph showing the appearance according to the number of layers in the CIGS solar cell to which the DBR film (blue) according to an embodiment of the present application is applied.
11B is a graph comparing reflectance spectra of DBR simulated by MATLAB at each point, CIGS solar cell to which DBR film is applied, and a glass substrate in one embodiment of the present application.
11c is a graph comparing reflectance spectra of DBR simulated by MATLAB at each point, CIGS solar cell to which DBR film is applied, and a glass substrate in one embodiment of the present application.
12A is a photograph showing the appearance according to the number of layers in a CIGS solar cell to which a DBR film (green) according to an embodiment of the present application is applied.
FIG. 12b is a graph comparing reflectance spectra of a DBR simulated by MATLAB at each point, a CIGS solar cell to which a DBR film is applied, and a glass substrate in an embodiment of the present application.
12c is a graph comparing reflectance spectra of DBR simulated at each point, CIGS solar cell to which DBR film is applied, and a glass substrate in one embodiment of the present application.
13A is a photograph showing the appearance according to the number of layers in a CIGS solar cell to which a DBR film (red) according to an embodiment of the present application is applied.
13B is a graph comparing reflectance spectra of a CIGS solar cell to which a DBR film is applied and a DBR simulated by MATLAB at each point, and a glass substrate, in an embodiment of the present application.
13c is a graph comparing reflectance spectra of DBR simulated by MATLAB at each point, CIGS solar cell to which DBR film is applied, and a glass substrate in one embodiment of the present application.
14A shows an appearance (i), a JV curve (ii), and an EQE spectrum (iii) in a CIGS solar cell to which a DBR film (blue) is applied according to an embodiment of the present application.
14B shows the appearance (i), JV curve (ii), and EQE spectrum (iii) in the CIGS solar cell to which the DBR film (green) is applied according to an embodiment of the present application.
14c shows the appearance (i), JV curve (ii), and EQE spectrum (iii) in the CIGS solar cell to which the DBR film (red) is applied according to an embodiment of the present application.

Throughout this specification, when a part is "connected" to another part, this includes not only the case of being "directly connected" but also the case of being "electrically connected" with another device interposed therebetween. do.

Throughout this specification, when a member is said to be located “on” another member, this includes not only a case in which a member is in contact with another member but also a case in which another member is present between the two members.

Throughout this specification, when a part "includes" a certain element, it means that other elements may be further included, rather than excluding other elements, unless otherwise stated.

As used herein, the terms "about," "substantially," and the like are used in a sense at or close to the numerical value when the manufacturing and material tolerances inherent in the stated meaning are presented, and to aid in the understanding of the present application. It is used to prevent an unconscionable infringer from using the mentioned disclosure in an unreasonable way.

As used throughout this specification, the term “step of doing” or “step of” does not mean “step for”.

Throughout this specification, the term "combination(s) of these" included in the expression of the Markush form means one or more mixtures or combinations selected from the group consisting of the components described in the expression of the Markush form, It means to include one or more selected from the group consisting of the above components.

Throughout this specification, reference to “A and/or B” means “A or B, or A and B”.

Hereinafter, embodiments and examples of the present application will be described in detail with reference to the accompanying drawings. However, the present application is not limited to these embodiments and examples and drawings.

A first aspect of the present disclosure provides a method for forming a first layer through a solution process of a first solution comprising a first layer precursor material; and forming a second layer through a solution process of a second solution containing a second layer precursor material, thereby preparing a unit laminate.

Specifically, since the color filter of the prior art is used in a CIGS solar cell, there is a problem in that color purity and light transmittance are inferior, or there is a problem in that the process cost is high because it is manufactured through a deposition process. However, the DBR filter manufacturing method according to the present invention can be performed at low cost by manufacturing a multilayer thin film through a low-temperature solution process, and a large-area DBR filter can be manufactured. In addition, the DBR filter prepared in this way not only expresses R, G, and B colors, but also has the effect of not lowering the light efficiency of the CIGS solar cell.

In one embodiment of the present application, the first layer and the second layer may be formed by performing spin coating of the first solution and the second solution, respectively, and drying. Specifically, the spin coating may be to use a polymer material instead of a metal material for the chuck of the spin coater. The polymer material may be polypropylene, polyvinyl chloride or polystyrene. When a polymer material is used for the chuck of the spin coater, there is an effect that can prevent the expression of the gradation color of the prepared film.

In one embodiment of the present application, the drying may be carried out at 30 ℃ to 90 ℃. Specifically, the drying is performed at 30 °C to 90 °C, 40 °C to 90 °C, 50 °C to 90 °C, 60 °C to 90 °C, 30 °C to 80 °C, 30 °C to 70 °C, 40 °C to 80 °C, 50 °C to 80 ℃ or 60 ℃ to 80 ℃ may be carried out. If the drying is carried out at less than 30 ℃, there is a problem that the drying time is too long, if the drying is carried out at a temperature exceeding 90 ℃, it cannot be considered a low-temperature process, and the drying may proceed quickly, but the film surface Cracks may occur and a problem in that the process cost is excessive may occur.

In one embodiment of the present application, the formation of the unit laminate may be repeated 3 times to form the 7th layer to 25 times to form the 51 layer. Specifically, the unit laminate may be formed as a plurality by laminating a plurality of times, and may be repeated 3 times to form 7 layers to 25 times to form 51 layers. When the DBR film is formed by repeating less than 3 times, the desired reflected wavelength width (FWHM) does not appear, and it may be formed by repeating more than 25 times. As this decreases, there may be a problem that the process efficiency is lowered.

In one embodiment of the present application, the first layer precursor material may be a metal oxide-ligand composite nanoparticle in which an acetylacetone ligand or a catechol ligand is coordinated to the surface of the metal oxide nanoparticle.

In one embodiment of the present application, the metal oxide-ligand composite nanoparticles may have a size of 10 nm or less, but is not limited thereto. For example, the size of the metal oxide-ligand composite nanoparticles is about 10 nm or less, about 8 nm or less, about 6 nm or less, about 4 nm or less, about 2 nm or less, about 1 nm to about 10 nm, about 2 nm to about 10 nm, about 3 nm to about 10 nm, about 4 nm to about 10 nm, about 5 nm to about 10 nm, about 6 nm to about 10 nm, about 7 nm to about 10 nm, about 8 nm to about 10 nm, about 9 nm to about 10 nm, about 1 nm to about 8 nm, about 3 nm to about 8 nm, about 5 nm to about 8 nm, about 7 nm to about 8 nm, about 1 nm to about 6 nm, from about 3 nm to about 6 nm, from about 5 nm to about 6 nm, from about 1 nm to about 4 nm, from about 3 nm to about 4 nm, or from about 1 nm to about 2 nm, including but not limited to not. In the metal oxide-ligand composite nanoparticles, the acetylacetone ligand or the catechol ligand is coordinated to the surface of the metal oxide nanoparticles, and the solvent dispersibility of the composite nanoparticles is excellent when preparing the first solution and the second solution There is a characteristic.

In one embodiment of the present application, the metal oxide may include one or more selected from TiO ₂ , WO ₃ , VO _{3 ,} and ZrO ₂ , but is not limited thereto.

In one embodiment of the present application, the acetylacetone ligand may include one represented by the following formula (1), but is not limited thereto:

[Formula 1]

.

.

In one embodiment of the present application, the catechol ligand may include one represented by the following formula (2), but is not limited thereto:

[Formula 2]

,

,

In Formula 1, R ¹ and R ² are the same as or different from each other, and each independently hydrogen; heavy hydrogen; halogen group; nitrile group; nitro group; hydroxyl group; carbonyl group; ester group; imid; amide group; a substituted or unsubstituted alkyl group; a substituted or unsubstituted cycloalkyl group; a substituted or unsubstituted alkoxy group; a substituted or unsubstituted aryloxy group; A substituted or unsubstituted alkylthio group; a substituted or unsubstituted arylthioxy group; a substituted or unsubstituted alkylsulfoxy group; a substituted or unsubstituted arylsulfoxy group; a substituted or unsubstituted alkenyl group; a substituted or unsubstituted silyl group; a substituted or unsubstituted boron group; a substituted or unsubstituted amine group; a substituted or unsubstituted arylphosphine group; a substituted or unsubstituted phosphine oxide group; a substituted or unsubstituted aryl group; Or a substituted or unsubstituted heterocyclic group.

In one embodiment of the present application, the acetylacetone ligand or the catechol ligand is coordinated to the surface of the metal oxide nanoparticles to prevent an increase in the size of the metal oxide nanoparticles.

In one embodiment of the present application, the second layer precursor material is polymethyl methacrylate (PMMA), polyimide, PDMS, poly acrylate, polyurethane acrylate (PUA) and silicon dioxide. (SiO ₂ ) It may include one or more selected from, but is not limited thereto.

In one embodiment of the present application, the refractive index of the first layer may be 1.6 to 2.0, and the refractive index of the second layer may be 1.0 to 1.5, but is not limited thereto. Specifically, the refractive index of the first layer may be 1.6 to 2.0 or 1.6 to 1.9, 1.6 to 1.8, and the refractive index of the second layer may be 1.0 to 1.5, 1.1 to 1.5, 1.2 to 1.5, or 1.3 to 1.5, However, the present invention is not limited thereto. The refractive index of the first layer may be larger than that of the second layer, and due to the difference in refractive index, the DBR film formed as a multilayer thin film can achieve a narrow reflection wavelength width (FWHM), and exhibit excellent reflectance to express color can do.

A second aspect of the present application is a color-type DBR film produced through the method for manufacturing a DBR film according to the first aspect, and expresses blue, green, and red colors by controlling the thickness of the first layer, the second layer, or both. It provides a color-type DBR film.

In one embodiment of the present application, the thickness of the first layer may be 20 nm to 50 nm, and the thickness of the second layer may be 100 nm to 180 nm. Specifically, the thickness of the first layer may be 20 nm to 50 nm, 30 nm to 50 nm, or 30 nm to 40 nm. In addition, the thickness of the second layer may be 100 nm to 180 nm, and more specifically, for blue expression, the thickness of the second layer is 100 nm to 140 nm, 100 nm to 130 nm, or 100 nm to 120 nm. nm, and for green expression, the thickness of the second layer may be 120 nm to 160 nm, 120 nm to 150 nm, or 130 nm to 150 nm, and for red expression, the thickness of the second layer is 150 nm to 180 nm, 160 nm to 180 nm or 160 nm to 170 nm. If the thickness of the first layer exceeds 50 nm, cracks may occur on the surface of the manufactured film, and if it is less than 20 nm, haze may occur in the manufactured film because it is too thin. Therefore, control of the thickness of the first layer and the thickness of the second layer is absolutely necessary for the formation of a high-quality film and color expression.

In one embodiment of the present application, the color DBR film has a reflection wavelength width (FWHM) of 70 nm or less for blue and green wavelengths, a reflection wavelength width for red wavelengths 100 nm or less, and a reflectance at the reflection wavelength It may represent 90% or more. Specifically, the color DBR film has a reflection wavelength width (FWHM) of 70 nm, 60 nm, or 50 nm or less of blue and green wavelengths, and a reflection wavelength width of 100 nm, 90 nm or 80 nm or less of a red wavelength, and , the reflectance at the reflection wavelength may be 90%, 92%, or 95% or more.

In one embodiment of the present application, since the color DBR film is a flexible polymer-based film, it has a feature that can be applied to a solar cell module having a curved surface rather than a flat surface.

A third aspect of the present application provides a CIGS solar cell to which the color DBR film according to the second aspect is applied. Specifically, the color DBR film according to the present application can be applied to a silicon solar cell, an organic solar cell, a perovskite solar cell, etc. other than a CIGS solar cell. However, the color filter of the prior art was applied to the silicon solar cell, etc., and showed adequate color efficiency and light efficiency, but when applied to a CIGS solar cell, the effect was not properly exhibited. However, the color-type DBR film according to the present application can exhibit high color purity and high transmittance even when applied to CIGS solar cells, so it is the only color-type DBR film that gives aesthetics to CIGS solar cells and does not reduce solar cell efficiency to less than 10%. There is this.

In one embodiment of the present application, the CIGS solar cell may be a building-integrated solar cell (BIPV), but is not limited thereto. Specifically, the color DBR film according to the present application has a high light transmittance when applied to a building-integrated solar cell, so that the efficiency of the solar cell can be maintained within 10% without lowering the efficiency, and at the same time, a narrow reflection wavelength width (FWHM) It can express colors with high color purity, so it can give aesthetics to the exterior walls of buildings.

In one embodiment of the present application, the CIGS solar cell, a substrate; a lower electrode layer disposed on the substrate; a light absorbing layer disposed on the lower electrode layer; an upper electrode layer disposed on the light absorbing layer; and a buffer layer disposed between the upper electrode layer and the light absorption layer.

In one embodiment of the present application, the CIGS solar cell may be any commercially available solar cell.

In the first to third aspects, content that may be common to each other may be applied to all of the first to third aspects even if the description thereof is omitted.

Hereinafter, the present invention will be described in more detail through examples of the present application, but the following examples are merely illustrative to aid understanding of the present application, and the content of the present application is not limited to the following examples.

[Example]

1. Example: Preparation of DBR film using solution process

1-1. TiO ₂ - Preparation of ACAC nanoparticles and PMMA solution

TiO ₂ -AcAc having a high refractive index was synthesized by mixing titanium n-butoxide (Ti(OBu ⁿ ) ₄ ) and acetylacetone (AcAc) in n-butanol. Then, an acidic aqueous solution of para-toluene sulfonic acid (PTSH) was added, and the mixture was stirred at room temperature for 15 minutes until the exothermic reaction was completed. After mixing at room temperature for 1 hour, the solution was heated at 60° C. overnight. The resulting solution was precipitated in toluene and centrifuged at 4000 rpm to obtain TiO ₂ -AcAc nanoparticles. The TiO ₂ -AcAc nanoparticles were then completely dried in a vacuum chamber for at least 5 hours and stored under ambient air. TiO ₂ -AcAc nanoparticles were dissolved in n-butanol at a concentration of 20-mg/ml and filtered using 0.1 μm polytetrafluoroethylene (PTFE) for further use.

Low refractive index polymethyl methacrylate (PMMA, Micro Chem, 950,000 MW, 4 wt% in anisole) was diluted with anisole at a ratio of 1:0.6 sol/sol for further use.

1-2. Preparation of DBR film

A first layer containing TiO ₂ -AcAc nanoparticles was deposited through spin coating in ambient air, dried on a hot plate at 70° C. for 2 minutes, cooled at room temperature for 1 minute, and a first layer with a thickness of 35 nm was obtained. Thereafter, a second layer having a different layer thickness was additionally laminated by spin coating PMMA in ambient air. Each layer was subjected to the same drying process by adjusting the thickness of each layer (115 nm for blue, 145 nm for green, 175 nm for red) for a desired color to obtain a pair. This step was repeated up to 37 layers.

The DBR film was produced in a size of 1 inch X 1 inch (Example 1) and 5 cm X 5 cm in size (Example 2).

2. Experimental Example 1: Confirmation of physical properties and appearance of DBR film

For the DBR film of Example 1 prepared above, the reflectance according to the number of layers was confirmed through simulation using MATLAB, and the color indicated by DBR was predicted through CIE to establish process conditions for DBR film lamination (FIGS. 3a to Figs. 3c and 4a to 4c). Referring to FIG. 3a, the thickness of the first layer containing TiO ₂ -AcAc nanoparticles is set to 35 nm and the thickness of the second layer containing PMMA is set to 110 nm, and these pairs are 9 (n = 9, 18). and 27), the reflectance was high in the spectrum of the blue wavelength, and it was confirmed that the blue series appeared in the CIE. In addition, referring to Figure 3b, the thickness of the first layer containing TiO ₂ -AcAc nanoparticles is set to 35 nm and the thickness of the second layer containing PMMA is set to 140 nm, and these pairs are 9 (n = 9) , 18 and 27), the reflectance was high in the spectrum of the green wavelength, and it was confirmed that the green series also appeared in CIE. In addition, referring to Figure 3c, the thickness of the first layer containing TiO ₂ -AcAc nanoparticles is set to 35 nm and the thickness of the second layer containing PMMA is set to 170 nm, and a pair of these is set to 9 (n = 9 , 18 and 27), the reflectance was high in the spectrum of the red wavelength, and it was confirmed that the red series appeared in the CIE.

In the above example, when the film was dried at a high temperature (180° C.), a problem occurred in that the film was cracked, and the film was dried at a low temperature (70° C.), and when the film was coated in the glove box, no color appeared. In addition, it was confirmed that haze occurred in the film when the humidity was high, and it was helpful to improve the uniformity and color purity of the film by replacing the spin coater chuck with polypropynyl. When the thickness of the first layer containing TiO ₂ -ACAC is thick, cracks occur, and when it is thin, haze occurs. It was confirmed that it is very important to set an appropriate range.

TEM and SEM were measured to observe the cross-sectional view of the DBR film. Since TEM and SEM using ion beam damage the cross-section of the DBR, making it impossible to measure, a small piece of DBR was resined with epoxy and measured using the microtome technique at low temperature. As a result of the measurement, it was confirmed that the cross section of the DBR film of Example 1 was evenly and well generated ( FIG. 5 ).

As a result of observing Example 2 having a size of 5 cm X 5 cm, it was confirmed that the reflectance and color were the same as those of Example 1 having a size of 1 inch X 1 inch even when coated on a large area ( FIGS. 6a to 6c ). The reflectance measured at the center (X ₁ , X ₄ ), the position 1.5 cm from the center (X ₂ , X ₅ ), and the position 3 cm radius from the center (X ₃ , X ₆ ) of the substrate of Example 2 were almost all It was confirmed that there was no difference ( FIGS. 6D and 6E ).

3. Example: CIGS solar cell to which DBR film manufactured using solution process is applied

A DBR film was laminated on the CIGS solar cell received from KIST under the continuous solution process conditions established in Examples 1 and 2. All manufacturing processes were carried out at a low temperature so as not to damage the CIGS solar cell and not to degrade the performance (Example 3).

4. Experimental Example 2: Confirmation of physical properties and appearance of CIGS solar cell to which DBR film is applied

As a result of coating a blue-based DBR film on a glass substrate and CIGS through a continuous solution process, both samples appear blue when more than a certain layer is coated (first layer 35 nm, second layer 110 nm), and the color increases as more layers are added. It became clearer (Fig. 7, Fig. 8a and Fig. 8b). However, all of them showed a circular gradation color at the center of the substrate, which was determined to be due to the temperature difference between the metal part and the rubber part in the chuck of the spin coater ( FIGS. 9A to 9D and Table 1 below).

[Table 1]

In addition, in order to prevent the formation of a gradation color due to the temperature difference, a chuck made of polypropylene was used. When looking at FIGS. 10A and 10B , gradation appeared in FIG. 10A using the metal chuck, but did not appear in FIG. 10B using polypropylene.

5. Experimental Example 3: Confirmation of performance of CIGS solar cell to which DBR film is applied

After applying the DBR films of R, G, and B colors to the CIGS solar cell, the reflectance of the CIGS color compared to the reference was maintained at 90% or more, and the reflected wavelength width (FWHM) was measured as blue, green < 70 nm, and red < 100 nm. (FIGS. 11A-11C, 12A-12B, and 13A-13C).

[Table 2]

Referring to Table 2 and FIGS. 14a to 14c, the CIGS solar cell of the example to which the DBR film of the example is applied compared the efficiency before and after film coating. It was confirmed that the decrease in efficiency was maintained within 10%, confirmed that the color could be expressed without lowering the efficiency of the CIGS solar cell.

The above description of the present application is for illustration, and those of ordinary skill in the art to which the present application pertains will understand that it can be easily modified into other specific forms without changing the technical spirit or essential features of the present application. Therefore, it should be understood that the embodiments described above are illustrative in all respects and not restrictive. For example, each component described as a single type may be implemented in a distributed manner, and likewise components described as distributed may also be implemented in a combined form.

The scope of the present application is indicated by the following claims rather than the above detailed description, and all changes or modifications derived from the meaning and scope of the claims, and their equivalents should be construed as being included in the scope of the present application. .

Claims (14)

forming a first layer through solution processing of a first solution comprising a first layer precursor material; and
Forming a second layer through a solution process of a second solution containing a second layer precursor material to prepare a unit laminate
As a method for producing a DBR film comprising a,
The first layer precursor material is a metal oxide-ligand composite nanoparticle in which an acetylacetone ligand or a catechol ligand is coordinated to the surface of the metal oxide nanoparticles,
The second layer precursor material may include at least one selected from polymethyl methacrylate (PMMA), polyimide, PDMS, poly acrylate, and polyurethane acrylate (PUA). Phosphorus, a method for producing a DBR film.
The method of claim 1,
Wherein the first layer and the second layer are formed through the steps of performing spin coating of the first solution and the second solution, respectively, and drying the DBR film manufacturing method.
3. The method of claim 2,
The drying will be carried out at 30 ℃ to 90 ℃, DBR film manufacturing method.
The method of claim 1,
The formation of the unit laminate is repeated 3 times to repeat 7 to 25 times to form a 51 layer, the method for producing a DBR film.
delete The method of claim 1,
The metal oxide-ligand composite nanoparticles will have a size of 10 nm or less, a method for producing a DBR film.
The method of claim 1,
The metal oxide is TiO ₂ , WO ₃ , VO _{3 ,} and ZrO ₂ A method of producing a DBR film comprising at least one selected from the group consisting of.
delete The method of claim 1,
The refractive index of the first layer is 1.6 to 2.0, and the refractive index of the second layer is 1.0 to 1.5, the method for producing a DBR film.
A color-type DBR film produced through the method of manufacturing the DBR film according to claim 1,
By controlling the thickness of the first layer, the second layer or both, to express blue, green, and red, a color DBR film.
11. The method of claim 10,
The thickness of the first layer is 20 nm to 50 nm,
The thickness of the second layer will be 100 nm to 180 nm, a color DBR film.
11. The method of claim 10,
The color type DBR film has a reflection wavelength width (FWHM) of 70 nm or less of blue and green wavelengths, a reflection wavelength width of red wavelength of 100 nm or less, and a reflectance of 90% or more at the reflection wavelength, Colorful DBR film.
A CIGS solar cell to which the color DBR film according to claim 10 is applied.
14. The method of claim 13,
The CIGS solar cell is a building-integrated solar cell (BIPV), CIGS solar cell.

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